The present invention is directed to a coupling fixture or device operationally releasably connecting one of a plurality of differently designed dental devices or parts, such as the dental handpiece, which requires at least a coolant and light at a head part thereof, to a supply which contains the various fluids and electrical supply for a lamp. The coupling fixture or device includes a coupling member which in a coupling condition is received in an acceptance sleeve of the dental handpiece or device and which has coolant moving in channels and the coolant is transferred from the coupling member into channels of the acceptance sleeve which channels convey the fluid to the head part of the dental device or handpiece. In addition, the coupling member has internal electrical lines extending to a electrical lamp adjacent the front end of the coupling member so that light can be coupled from the coupling member to a light conductor in the dental device to be carried to the head thereof and also has an electrical arrangement on the coupling member to enable coupling electrical power to the dental device.
A coupling fixture or device where various different styles of handpieces such as turbine handpieces, spray handpieces, miniature motor handpieces and ultrasound handpieces can be optionally coupled to and uncoupled from a coupling part connected to a supply hose is disclosed in U.S. Pat. No. 4,080,737. In this coupling fixture, the coupling and uncoupling can be accomplished without the assistance of tools. In addition, to the agents such as air and water plus electrical power, light can also be transmitted at the coupling location. For the transmission of light, light supplying element in the form of an optical fiber or waveguide is disposed in the center of the coupling pin or tenon of the coupling member and a light receiving element, which may also be an optical fiber waveguide, is disposed in the end face of the handpiece. In the coupled condition of the handpiece and the coupling member, the ends of the light supplying optical fiber and the light receiving optical fiber are positioned opposite one another in a correspondingly optically coupled manner.
Another coupling fixture or device of a similar type is disclosed in U.S. Pat. No. 4,398,885. In this coupling device, the light supplying element is a lamp, which is operated through an electrical current. The lamp is mounted at the center of an end face of the pin-shaped coupling member in a correspondingly fashion lamp socket to which the electrical leads extend.
In addition to the above two types of arrangement for supplying light to a head of a dental device, another type is known where the lamp is disposed on the handpiece expediently in the proximity of the treatment head (See German AS No. 10 68 425). The voltage supply from the coupling member to the handpiece occurs through coacting concentrically disposed slip rings and wiper contacts which are arranged in the coupling member and handpiece.
The first two arrangements, where the lamp is positioned on either the coupling member or the hose side of the coupling member, have advantages that only one lamp need be provide given use of various handpieces in contrast to the last mentioned arrangement wherein a lamp must be provided for each handpiece. Another advantage of the first two arrangements are that no voltage carrying parts can be contacted with the removal of the handpiece and that the handpiece themselves need not be equipped with electrical contacts, lines or lamps. However, the arrangement of the lamp at the hose side of the coupling member is not appropriate for every case. An example of such a case is when as illustrated and disclosed in U.S. Pat. No. b 4,278,428, the handpiece itself is designed as a multipart handiece and only the head part provided with different gearing graduations or ratios is interchangeable. With such an arrangement, the parting location also required in a light relaying part of the handpiece would involve a not negligible light loss which due to the structure of the handpieces cannot usually be compensated by either a more powerful and hence larger lamp or by a light conductor having a larger cross-section.